Portable derrick



placed in position, and it is particularly PATENT OFFICE.

PETER 'RABBITig or 'JACKsoiIvILLE7 ILLINOIS.

PORTABLE DERRICK.

SPECIFICATION forming part of Letters Patent N o. 377,576. dated February '7, 1888. Application le'd J' une 4, 1887. Serial No. 240,296. (No model.)

To all whom it may concern.-

Be it known that I, PETER RABBITT, a citizen of the United States, residing at Jacksonville, in the county of Morgan. and State of Iliinois, have invented certain new and useful Improvements in Portable Derricks; and I do hereby declare the following to be a full, clear, and exact description of the invention,'such as will enable others skilled in the art to which it appertains to make and use the same.-

My invention relates toimprovementsin portable derricks by which stone or other heavy bodies may be easily and readily handled and adapted for the setting of curbstones for pavements and for the building of deep sewers; and it consists in the construction and combination of parts, hereinafter disclosed inthe description and claims.

The object of my invention is to provide a portable derrick which can be readily used where the surface of the ground is broken or uneven, which can set a considerable number of pieces of stone in line without the necessity of moving it for the setting of each piece, which can be cheaply manufactured, and which is simple, strong, easily handled, and not liable to get out of` order. I attain this object by the mechanism illustrated in the accompanying drawings, in which the same referenceletters indicate the saine part-s, and in which- Figure 1 represents a side elevation of one end of the niachine, the other end-being broken away.- Fig. 2 is an end elevation, and Fig. 3 is a broken elevation showing the inner side of one of the legs.

In the drawings, A represents the upper beam, and B the lower or track beam. The upper beam, A, and the legs or standards C C, which are bolted to a beam at their tops and held in position by the rods F, D, and E, con- Stitute the frame of the machine. The upper beam, A, may be of any length desired. I have found eighteen feet to be a suitablelength for ordinary purposes. It is braced or trussed by two iron rods, F F. Beneath the upper beam, A, is suspended the lower or track beam, B, by means of hinged or knucklejointed bolts GG, which allow said track-beam to swing through considerable space, either laterally or longitudinally. This lower trackbeam is rabbeted on both of its upper corners or edges, and tracks of' iron, b b, are secured in the rabbets, and upon. which any ordinary carriage or traveler may run.

On theinsi'des of the legsor standards G C are placed the extension pieces or legs H H, as shown in Figs. 2 and 3. 4These extension pieces or legs have longitudinal slots I, asv

shown in Fig. 3, which allowthem to be slid up and down on the tail-bolts JJand the rods D. These rods have nuts don their ends outside of the legs or standards C C, to prevent them from spreading, and nuts d on theinsides of the extension-legs H H, to hold them in position when adjustedv or extended. The lower ends of these extension-legs are heldin position by the tail-bolts .I J, which have nuts j j and jj on the inside and loutside of said legs, thus form-ing clamps, the inside nuts, j j, being elongated and having tangs or teeth on their `inner faces for engaging with the wood and preventing said legs from slipping.

The manner of using my improved derrick is as follows: When used for setting curbstones, it is placed with the track-beam over and4 either in line with or across the line in which said stones require to be set. Upon the track-beam is placed any ordinary carriagel or traveler, from which is swung a swivel hoist or pulley, grapnel, &c. In case the der-v rick be placed on aline with the line of curbing, the length of the beam allows a considerable stretch of stone to be laid without shifting the machine, and in case it be placed across said line the length of the beam allows l of the picking up of the stones from some distance and carrying the same by means of the carriage or traveler to the proper position, Y

and in either position of the derrick it permits the accurate, easy, and speedy adjustment and placement of the stones in place.

As .the track-beam is yieldinglysuspended from the top beam by the hinged bolts, they allow considerable lateral movement thereof,

thus insuring a level track for the carriage or Y traveler, even though one side ofthe machine is considerably lower than the other.

In case the ground is uneven, one or more of the legs or standards may be lengthened by loosening the clamp or tail-bolt J and running the inside or extension leg H down until it meets the requirements of the case. The top of the machine may also be thrown or shifted some distance sidewise by lengthening both legs on one side and still preservea level track for the carriage-travel er.

Having thus fully described my invention,

1. A portable derrick comprising the upper or top beam, A, the laterally and longitudinally movable lower or track beam, B, the trussing and bracing rods E E and F F, the standards C C, and the longitudinally-slotted adjustable legs H H, substantially as and for the purpose described.

2. A portable derrick comprising the upper or top beam, A, the laterally and longitudinally movable lower or track beam, B, the trussing and bracing rods E E and F F, the knuckle-j ointed bolts G G, the longitudinallyslotted adjustable legs H H, and the standards C C, substantially as described.

3. Aderrick provided with the legs or standards C C, the extension-legs H H, formed with the longitudinal slots I I, the rods D D, pro

vided with the nuts d and d', arranged on the 25 outside and inside of said legs, and the tailbolts J J, provided with the nuts jj and jj, the latter being elongated and having teeth or projections on their inner faces, substantially as and for the purpose described.

4. A portable derrick comprising the top beam, A, the laterally and longitudinally movable track-beam B, the knucklejointed bolts G G, the legs or standards C C, the extensionlegs H d d', the tail-bolts J J provided with the nuts j j and jj, and the trussing or bracing rods E E and F F, substantially as described.

In testimony whereof I aflix my signature in presence of two witnesses.

PETER RABBITT.

XVitnesses:

IsAAo C. CoLEMAN, DAN. E. PmRsoN.

H, rods D D, provided with the nuts 35 

